On 1/25/19 11:41 AM, Eike Armbrust wrote: > For the third time in the last three months one of our mail servers was > blacklisted by T-Online. In all cases the reason for being blacklisted was > that users had an automated forwarding to T-Online and one(!) uncaught spam > email got forwarded.
If you ever need some examples of a blacklist removal request, I can easily provide one to you (email is included). I never had any reply to my answers... François ---- From: Deutsche Telekom Postmaster <postmas...@t-online.de> To: <postmas...@free.fr> Subject: Blocking e-mails from Deutsche Telekom Date: Mon, 27 Aug 2018 15:05:47 +0200 Dear Sir or Madam, esteemed colleagues, we have received reports from our customers indicating that your mail system is blocking at least one of our mail server IP adresses from sending mail to your system. Example: | <%redact...@free.fr>: host mx2.free.fr[212.27.42.59] said: | 451 too many errors from your ip (194.25.134.21), please visit | http://postmaster.free.fr/ (in reply to DATA command) Outgoing emails are directed compulsory through a spam filter. But of course there is no spam filter which separates 100% spam. We go to any lengths to reduce the load of other systems to the least possible degree. But you cannot change the parameters in an arbitrary manner because an automatic spam filter would reject more and more emails as 'spam' which aren't spam. It is an official internet standard of the 'Internet Engineering Taskforce' (IETF) that the operator of the receiving mail server (and not the operator of a block list) is solely responsible for the rejection of emails: It is the responsibility of the system administrators who adopt one or more DNSBLs to evaluate, understand, and make a determination of which DNSBLs are appropriate for the sites they administer. If you are going to allow a third party's information to guide your filtering decision-making process, you MUST understand the policies and practises of those third parties because responsibility for filter decisions remains ultimately with you, the postmaster. Source: http://tools.ietf.org/html/rfc6471#section-1.2 The mailservers ... 194.25.134.16 - 194.25.134.22 (private & small business users) 194.25.134.80 - 194.25.134.85 (private & small business users) 194.25.134.10 - 194.25.134.11 (business users) ... of Deutsche Telekom AG are used by approx. 20 million individual customers and some hundred thousands of domains of business customers. According to conservative estimates, about one percent of all end-user computers are infected with malicious software. Therefore we cannot avoid relaying a certain proportion of "spam". But please bear in mind that not only our millions of customers are the one to suffer for a too strict blocking policy but also all the customers of other providers (which are using your blacklist) when they lose the email contact to their friends, business partners, customers or employees. Deutsche Telekom ... • applies content filtering for outgoing and incoming emails • avoids backscattering by refusing acceptance of emails to unknown users and of emails categorized as "spam" by the content filtering system • put locks to spamming email accounts without prior warning to the responsible bearer of the account. Written as above, we do enforce our AUP, which includes disconnection. If there is an abuse issue that we need to deal with, please send full header information and message to ab...@telekom.de and our abuse team will investigate immediately. Apropos: The possibly complex maintenance of an own whitelist can be circumvented by the probably most relevant whitelist, the DNSWL www.dnswl.org. At http://dnswl.org/s?s=1972 you'll find our mailservers. Thanks in advance for a complaisant examination of our concern! Kind regards ---- _______________________________________________ mailop mailing list mailop@mailop.org https://chilli.nosignal.org/cgi-bin/mailman/listinfo/mailop
